The Singer/Friden 1162 is a wonderful
machine, developed as an integrated circuit-based remake of Friden's
first-generation transistorized electronic calculator, the
Friden 132. As a result of the
use of integrated circuits in the machine, the 1162 is significantly smaller
and lighter than the EC-132, and while still rather heavy, is also easier
to lug around than the 132. The 1162 is a stable-mate to the Friden 1160,
which is the IC-based remake of the original Friden
130 calculator. The original Friden 130 provided a four-function
calculator with memory register, and the 132 added a one-touch
square root function. The 1160 mirrors the four-function capabilities
of the Friden 130, and adds a nice sum of products function [X+], while the 1162
replaces the [X+] key with the one-touch square root
function of the Friden 132. Along with the 1160 and 1162, Singer/Friden offered
the Model 1166, a lower-cost machine targeted at the business/accounting
market, with reduced the number of digits of capacity (13 versus 14).
The 1166 also features leading zero suppression, a feature that made the
machine more friendly for non-technical users. According to pricing information
published in early 1971, prices of the 116x-series calculators started
with the 1162 at the high-end, with a price of $1195, $995 for the 1160,
and $795 for the 1166.

The museum has two examples of this machine, one fairly early production machine made in late 1968, and another later
machine built sometime in the late part of 1969, with these dates based on
date codes on various parts of the machines.

Inside View of Singer/Friden 1162

The 1162 shares the CRT tube display
technology used in the earlier 130/132 calculators, but uses a smaller CRT tube
(Type 3WP1), and dispenses with the display
of all levels of the four-level RPN stack. Instead, the machine displays
the bottom two working registers of the stack, leaving the top two
registers of the stack invisible. This allows the use of the smaller CRT tube,
which further reduces the physical size of the calculator.

Close-up of 1162 CRT Display

The digits are "drawn" on the CRT
display in a
slightly different fashion than the earlier 130/132 calculators.
A major difference between the 1162
and the earlier calculators is that the digits on the display are
grouped in threes (except while entering a number) to make reading and
recording results easier for humans.

The intricate mechanical keyboard encoding mechanism

The 1162 provides the standard four
functions and square root, along with a store/recall memory register. The machine
has a capacity of 14-digits plus sign, one more digit than its predecessor.
Decimal point location is fixed, and is set by a rotary thumbwheel that
allows selection of decimal point location from 0 to 11 digits behind the
decimal point. The keyboard is a shrunken down and somewhat less robust
version of the complex, mechanically encoded keyboard on the Friden 130/132
machines, with keys that lock down (by virtue of a solenoid-activated
mechanism) while operations are in progress. The 1162 forsakes the combination
overflow indicator/unlock keyboard key of the 130/132, opting instead
for a keyboard panel-mounted incandescent indicator which lights to indicate
overflow conditions, and use of the [CLEAR] key to reset the machine in such
conditions.

One of the 1162 Circuit Boards

The 1162 uses small-scale integration IC's for the majority of its logic.
Most of the chips are made by Texas Instruments, with a few Fairchild chips
sprinkled in here and there. The machine is made up of a mix of very early
7400-series TTL IC's (mostly 7474 dual flip-flops), along with another line
of early TI Small-Scale DTL (Diode-Transistor Logic) chips in the SN158XX
series (For example: SN15862[Triple 3-Input NAND], SN15830[Expandable Dual
4-Input NAND], and SN15846[Quad 2-Input NAND]). Along with the compliment
of small-scale IC's, the 1162 (as well as other machines in the 116x line)
use a medium-scale integration devices custom made by Texas Instruments for
Singer/Friden. The chips consist of part numbers SN1286, SN1287,
and SN1288. Each chip implements one of the three up/down
counters used in the "three-counter" architecture of the machines.

The Singer/Friden 1162 utilizes a total of 93 IC's, along with a significant
compliment of transistors, diodes, resistors and capacitors. The main
logic of the machine is spread across six circuit boards which are situated
vertically in a card cage, plugging into a backplane made from an etched
circuit board. The backplane board also contains some power supply
circuitry. An additional circuit board mounted near the CRT provides high
voltage (e.g.: deflection amplifier) CRT drive functions.

The Delay Line (in aluminum housing) and Delay Line Driver/Amplifier Board

Even though IC's had replaced the all-transistor electronics of the
earlier 130/132 machines, the 1162 still uses a magnetostrictive delay
line technology for storing the working registers of the machine.
The delay line of the 1162 is contained in an aluminum housing in the
bottom of the machine, as in the 130/132, but the whole assembly is
significantly smaller that its counterpart in the 130/132.
The delay line in the 116x-series machines is simplifed in design from
that used in the 130/132 calculators, with less mechanically complex
transducers and simplified driver circuitry. The delay line material is
a beryllium-copper alloy wire approximately 40-feet in length, with a smaller
diameter than that used in the 130/132 calculators, allowing the overall
delay line package to be about two-thirds smaller in volume than the
130/132 delay line. The delay line in the 116x-series calculators has a
delay period of approximately 4 milliseconds.

Inside a Friden 116x-Series Delay Line

The delay line was still needed, as the cost of enough integrated circuits to
hold all of the bits required to represent all of the working registers
of the machine was simply too high to be cost effective back in the late
1960's. For more information on the way that the 1162 and the 130/132
machines keep track of the registers using this acoustic delay line
technology, please have a look at the
Friden 130
exhibit.

Singer/Friden 1162 Keyboard Detail

The 1162 operates much the same as the Friden EC-132. The keyboard
nomenclature differs, but the functionality is very similar. Numbers
are always entered into the bottom register (the bottom number on the
display) of the stack. The [ENTER] key of the 130/132 is replaced with
a key labelled [FIRST NUMBER/CHG SIGN]. This key is a dual function key.
The first press enters the number in the bottom register of the stack.
A successive press will negate the number. The 130/132 opted for a
separate [CHANGE SIGN] key to change the sign of the entered number.
The [DUP] key duplicates the number in the bottom register of the stack, and
pushes the stack up. The [I] key swaps the content of the
bottom two (the registers shown on the display) stack registers.
The [TO MEMORY] button stores the content of the bottom of the stack
into the memory register (popping the stack), and the [FROM MEMORY]
recalls the memory register into the bottom of the stack (pushing the stack).
The [CLEAR] key pops the stack, and also serves to clear the "OVERFLOW"
indicator, and the [CLEAR STACK] key zeroes out all four registers of
the stack.

Another Internal View

Though implemented with integrated circuits, the 1162 isn't dramatically faster
than its all-transistor predecessor. The design of the machine
was essentially a re-implementation of earlier Friden transistorized
design using IC technology. In practice the 1162 is
just marginally faster than the 132. The basic clock frequency of the
116x-series calculators is 2.8MHz, but this fundamental frequency
is divided down to 700KHz to make the master clock frequency, over double
the clocking speed that 130/132 operate at. In spite of this, the 1162
isn't all that much faster than its transistorized big-brother.

All 9's divided by 1 takes a shade over 1 second, and square root
operations can take from perhaps 1/4 second to 1 1/2 seconds, depending on
the argument. During calculations, the display is blanked, and the function
key is locked down until the operation is complete. Overflows lock the
keyboard until the overflow condition is cleared with
the [CLEAR] or [CLEAR STACK] keys. Division by zero results in the machine
locking up, with recovery possible with the [CLEAR STACK] key.
Extracting the square root of a negative number simply returns an answer
as if the argument was positive.

After the 116x-series machines were
introduced, the next generation of calculators from Friden were designed and
manufactured by Hitachi in Japan, with Singer/Friden logos placed on them
for sale by the Friden division of Singer. The 1162 and the other machines
in the 116x and 115x series calculators are the last of the legacy
that started with Robert Ragen's design for the Friden EC-130.

Extremely Rare Item Counter OptionImage Courtesy Gerard Timmerman

Gerard Timmerman, a fellow collector who lives in the Netherlands, has come
across an extremely unusual Friden 1162. It has a Friden-made Item Counter
built into the machine. The item counter consists of a circuit board mounted
across the front of the machine, to the right of the CRT. The board has
four TTL IC's, and one DTL IC on it that implement a simple two digit decimal
counter, with two small seven-segment LED displays that shine through red
window in a
cutout on the front panel of the 1162 to provide a count of the number
of entries made into the calculator. When the [CLEAR STACK]
key is pressed, the counter is cleared. The counter is incremented when
the [FIRST NUMBER/CHG SIGN] key is pressed, or when a math operation
key is pressed (excluding square root). The Item Counter was useful
for statistical operations, such as performing averages, as well as
for invoicing calculations. The item counter appears to be an add-on, not
something that could be ordered on a 116x-Series calculator from the
factory. I have not been able to find any documentation on the item
counter for the 116x-Series calculator, but the fact that Gerard's machine
has the option, and the circuit board for the item counter clearly identifies
the board as SINGER Part Number 7016765 Rev 1, is a clear indication that
this rare item was a real product. Sincere thanks to Gerard Timmerman
for providing the photo of this extremely rare addition to his Friden 1162.